Flat battery

Patent metadata

Field	Value
Publication number	US-11201367-B2
Application number	US-201816113945-A
Country	US
Kind code	B2
Filing date	Aug 27, 2018
Priority date	Sep 18, 2008
Publication date	Dec 14, 2021
Grant date	Dec 14, 2021

Abstract

A flat battery of the present invention is a flat battery including an exterior can and a sealing can with which an opening of the exterior can is sealed, wherein the exterior can and the sealing can include a bottom portion and a circumferential wall extending upright from an outer circumference of the bottom portion and have a cylindrical shape that is open at one end; a distal end portion of the circumferential wall of the exterior can is bent toward a central axis of the sealing can to form a curve, whereby the exterior can is fixed to the sealing can by crimping; in a cross-sectional shape of the sealing can in the direction of the central axis, the circumferential wall of the sealing can is a single layer wall without being folded back, and the circumferential wall of the sealing can includes a rectilinear portion that is connected to the bottom portion via a corner portion; and an angle θ1 formed by the bottom portion and the rectilinear portion may be greater than 90°.

First claim

The invention claimed is:

1. A method for manufacturing a flat battery comprising an exterior can and a sealing can that seals an opening of the exterior can, comprising:
(a) a step of forming the exterior can that comprises a bottom portion and a first circumferential wall extending upright from an outer circumference of the bottom portion and that has a cylindrical shape open at one end;
(b) a step of forming a sealing can that comprises a planar portion and a second circumferential wall extending upright from an outer circumference of the planar portion and that has a cylindrical shape open at one end, the second circumferential wall having a rectilinear portion connected to the planar portion via a corner portion, the rectilinear portion being constituted by a perfectly straight line or a curved line having a radius of curvature that is 20 or more times as great as a radius of the corner portion, wherein the second circumferential wall is a single layer wall without being folded back, and an angle θ2 formed by the planar portion and the rectilinear portion is greater than 90°; and
(c) a step of bending a distal end portion of the first circumferential wall of the exterior can that is formed in the step (a) toward a central axis of the sealing can that is formed in the step (b) to form a curve, and thus the exterior can is fixed to the sealing can by crimping, wherein the second circumferential wall of the sealing can is deformed so that an angle θ1 formed by the planar portion and the rectilinear portion is smaller than the angle θ2 and 95° or less.

2. The method for manufacturing a flat battery according to claim 1 , wherein a difference θ2−θ1 between the angle θ2 and the angle θ1 is between 0.5° and 5° inclusive.

3. The method for manufacturing a flat battery according to claim 1 , wherein the angle θ2 is between 92° and 98° inclusive.

4. The method for manufacturing a flat battery according to claim 1 , wherein the angle θ1 is greater than 90°.

5. A method for manufacturing a flat battery comprising an exterior can and a sealing can that seals an opening of the exterior can, comprising:
(a) a step of forming the exterior can that comprises a bottom portion and a first circumferential wall extending upright from an outer circumference of the bottom portion and that has a cylindrical shape open at one end;
(b) a step of forming a sealing can that comprises a planar portion and a second circumferential wall extending upright from an outer circumference of the planar portion and that has a cylindrical shape open at one end, the second circumferential wall having a rectilinear portion connected to the planar portion via a corner portion, the rectilinear portion being constituted by a perfectly straight line or a curved line having a radius of curvature that is 20 or more times as great as a radius of the corner portion, wherein the second circumferential wall is a single layer wall without being folded back, and an angle θ2 formed by the planar portion and the rectilinear portion is greater than 90° and 98° or less; and
a step of bending a distal end portion of the first circumferential wall of the exterior can that is formed in the step (a) toward a central axis of the sealing can that is formed in the step (b) to form a curve, and thus the exterior can is fixed to the sealing can by crimping, wherein the second circumferential wall of the sealing can is deformed so that an angle θ1 formed by the planar portion and the rectilinear portion is smaller than the angle θ2.

6. The method for manufacturing a flat battery according to claim 5 , wherein a difference θ2−θ1 between the angle θ2 and the angle θ1 is between 0.5° and 5° inclusive.

7. The method for manufacturing a flat battery according to claim 5 , wherein the angle θ2 is 92° or more.

8. The method for manufacturing a flat battery according to claim 5 , wherein the angle θ1 is greater than 90°.

9. The method for manufacturing a flat battery according to claim 5 , wherein the angle θ1 is 95° or less.

Assignees

• Maxell Holdings Ltd

Inventors

• Yamaguchi Koji
• Yabushita Noriyuki
• Yoshiba Toshikazu
• Tsuda Kenji

Classifications

• H01M50/167

  by crimping · CPC title

• H01M50/171

  using adhesives or sealing agents · CPC title

• Y10T29/4911

  including sealing · CPC title

• H01M50/109 Primary

  of button or coin shape · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title